Is initially after a dry and cold room (5)
I believe the answer is:
attic
'room' is the definition.
(type of room)
'is initially after a dry and cold' is the wordplay.
'initially' says to take the initial letters.
'after' says to put letters next to each other.
'a dry' becomes 'att' (I've seen this in other clues).
'and' is a charade indicator (letters next to each other).
'cold' becomes 'C' (eg on taps).
The first letter of 'is' is 'i'.
'i' after 'att' is 'atti'.
'atti'+'c'='ATTIC'
(Other definitions for attic that I've seen before include "Room at the top of a house" , "top-flight accommodation" , "Athenian - garret" , "Lofty room" , "Tacit (anag.)" .)